The Yahoo effort (search.yahoo.com) . . . is so impressive I'm going to make it my default searcher. Best is "Search Assist," an expandable box right below where you type your query that offers a bevy of clickable terms to help you refine it. A good reference librarian will write a specific, targeted search. Yahoo's search assist gets you close to librarian status, without the bother of getting an MLS degree.Not that I want to suggest that an MLS is a bother, mind you . . .